Toners containing crystalline or semi-crystalline polyester resins with at least one amorphous resin have recently been shown to provide very desirable ultra low melt temperature fusing, which is important for both high-speed printing and lower fuser power consumption. These types of toners containing amorphous and crystalline polyesters have been used for both emulsion aggregation (EA) toners, and in conventional jetted toners. Combinations of amorphous and crystalline polyesters may provide toners with relatively low-melting point characteristics (sometimes referred to as low-melt, ultra low melt, or ULM), which allows for more energy-efficient and faster printing.
Emulsion aggregation coalescing processes for the preparation of toners are illustrated in a number of patents, such as U.S. Pat. Nos. 5,290,654, 5,278,020, 5,308,734, 5,344,738, 6,416,920, 6,576,389, 6,593,049, 6,743,559, 6,756,176, 6,830,860, 7,029,817, and 7,329,476, and U.S. Patent Application Publication Nos. 2006/0216626, 2008/0107990, 2008/0107989, 2008/0236446, and 2009/0047593. The disclosures of each of the foregoing patents are hereby incorporated by reference in their entirety.
It has been previously disclosed that polyester toner particle growth may be stopped or frozen by adjusting the pH of the solution followed by the addition of ethylene diamine tetraacetic acid (EDTA) sodium salt as a chelating agent. Some of the methods for freezing growth followed by chelating agent addition may negatively impact other properties of the toner particles, such as triboelectric charge and image gloss of the toner particles. It would thus be advantageous to provide an additive in addition to adjusting the pH that effectively controls polyester-based toner particle size and resulting image gloss on a substrate without adversely affecting other useful properties of the toner.